The number of osteoporosis patients is increasing with increasing in aged population, and public concern is now focused on osteoporosis. In this circumstance, an osteoporosis examination is one of objectives of the Law of Health and Medical Services System for the Aged and has been made by various medical facilities including a public health center.
The osteoporosis examination uses the DXA method which can measure a bone mass of a lumbar vertebra, radius, and femur neck by dual energy X-ray, the MD method which measures a bone mass of the cortical bone of the metacarpal bone by dual energy X-ray, or a ultrasonic method which uses no X-rays. The DXA method can perform an accurate diagnosis based on detailed data, but requires an expensive and large device. The MD method or the ultrasonic method can simply make a measurement, but is poor in accuracy. In particular, the ultrasonic method causes a large measurement error.
Therefore, an osteoporosis diagnosis method or device which can simply and accurately make a measurement has been required. As for the ultrasonic method, Patent Document 1 or 2 discloses an osteoporosis diagnosis device and method which can improve a measurement accuracy of a bone density. On the other hand, the advancement of the medical study on osteoporosis has revealed that a form of the cortical bone of a mandible forming a mandibular bone is changed with a lowered bone density, and Patent Document 3 discloses an osteoporosis diagnosis support device using panoramic radiographs performed in a dental treatment as means judging the presence or absence of osteoporosis from the changed state of the form of the cortical bone of the mandible.    Patent Document 1: JP-A-8-215196    Patent Document 2: JP-A-11-313820    Patent Document 3: JP-A-2004-209089